diff mbox

[v16,10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code to prepare for GTDT

Message ID 1479304148-2965-11-git-send-email-fu.wei@linaro.org (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

fu.wei@linaro.org Nov. 16, 2016, 1:49 p.m. UTC
From: Fu Wei <fu.wei@linaro.org>

The patch refactor original memory-mapped timer init code:
    (1) Extract a subfunction for detecting a bast time frame:
        is_best_frame.
    (2) Refactor "arch_timer_mem_init", make it become a common code for
        memory-mapped timer init.
    (3) Add a new function "arch_timer_mem_of_init" for DT init.

Signed-off-by: Fu Wei <fu.wei@linaro.org>
---
 drivers/clocksource/arm_arch_timer.c | 162 +++++++++++++++++++++++------------
 1 file changed, 107 insertions(+), 55 deletions(-)

Comments

Mark Rutland Nov. 18, 2016, 8:03 p.m. UTC | #1
On Wed, Nov 16, 2016 at 09:49:03PM +0800, fu.wei@linaro.org wrote:
> From: Fu Wei <fu.wei@linaro.org>
> 
> The patch refactor original memory-mapped timer init code:
>     (1) Extract a subfunction for detecting a bast time frame:
>         is_best_frame.

Please leave this logic in arch_timer_mem_init(). Pulling it out gains
us nothing, but makes the patch harder to review.

>     (2) Refactor "arch_timer_mem_init", make it become a common code for
>         memory-mapped timer init.
>     (3) Add a new function "arch_timer_mem_of_init" for DT init.

These generally look fine.

Thanks,
Mark.

> Signed-off-by: Fu Wei <fu.wei@linaro.org>
> ---
>  drivers/clocksource/arm_arch_timer.c | 162 +++++++++++++++++++++++------------
>  1 file changed, 107 insertions(+), 55 deletions(-)
> 
> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
> index 9ddc091..0836bb9 100644
> --- a/drivers/clocksource/arm_arch_timer.c
> +++ b/drivers/clocksource/arm_arch_timer.c
> @@ -923,17 +923,35 @@ static int __init arch_timer_of_init(struct device_node *np)
>  CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
>  CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
>  
> -static int __init arch_timer_mem_init(struct device_node *np)
> +static bool __init is_best_frame(void __iomem *cntctlbase, u32 cnttidr, int n)
> +{
> +	u32 cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT | CNTACR_RWVT |
> +		     CNTACR_RVOFF | CNTACR_RVCT;
> +
> +	/* Try enabling everything, and see what sticks */
> +	writel_relaxed(cntacr, cntctlbase + CNTACR(n));
> +	cntacr = readl_relaxed(cntctlbase + CNTACR(n));
> +
> +	if ((cnttidr & CNTTIDR_VIRT(n)) &&
> +	    !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT)))
> +		arch_timer_mem_use_virtual = true;
> +	else if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
> +		return false;
> +
> +	return true;
> +}
> +
> +static int __init arch_timer_mem_init(struct arch_timer_mem *timer_mem)
>  {
> -	struct device_node *frame, *best_frame = NULL;
>  	void __iomem *cntctlbase, *base;
> -	unsigned int irq, ret = -EINVAL;
> +	struct arch_timer_mem_frame *best_frame = NULL;
> +	unsigned int irq;
>  	u32 cnttidr;
> +	int i, ret;
>  
> -	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
> -	cntctlbase = of_iomap(np, 0);
> +	cntctlbase = ioremap(timer_mem->cntctlbase, timer_mem->size);
>  	if (!cntctlbase) {
> -		pr_err("Can't find CNTCTLBase\n");
> +		pr_err("Can't map CNTCTLBase.\n");
>  		return -ENXIO;
>  	}
>  
> @@ -943,76 +961,110 @@ static int __init arch_timer_mem_init(struct device_node *np)
>  	 * Try to find a virtual capable frame. Otherwise fall back to a
>  	 * physical capable frame.
>  	 */
> -	for_each_available_child_of_node(np, frame) {
> -		int n;
> -		u32 cntacr;
> -
> -		if (of_property_read_u32(frame, "frame-number", &n)) {
> -			pr_err("Missing frame-number\n");
> -			of_node_put(frame);
> -			goto out;
> -		}
> -
> -		/* Try enabling everything, and see what sticks */
> -		cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT |
> -			 CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT;
> -		writel_relaxed(cntacr, cntctlbase + CNTACR(n));
> -		cntacr = readl_relaxed(cntctlbase + CNTACR(n));
> -
> -		if ((cnttidr & CNTTIDR_VIRT(n)) &&
> -		    !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) {
> -			of_node_put(best_frame);
> -			best_frame = frame;
> -			arch_timer_mem_use_virtual = true;
> -			break;
> +	for (i = 0; i < timer_mem->num_frames; i++) {
> +		if (is_best_frame(cntctlbase, cnttidr,
> +				  timer_mem->frame[i].frame_nr)) {
> +			best_frame = &timer_mem->frame[i];
> +			if (arch_timer_mem_use_virtual)
> +				break;
>  		}
> -
> -		if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
> -			continue;
> -
> -		of_node_put(best_frame);
> -		best_frame = of_node_get(frame);
>  	}
> +	iounmap(cntctlbase);
>  
> -	ret= -ENXIO;
> -	base = arch_counter_base = of_iomap(best_frame, 0);
> -	if (!base) {
> -		pr_err("Can't map frame's registers\n");
> -		goto out;
> +	if (!best_frame) {
> +		pr_err("Can't find frame for register\n");
> +		return -EINVAL;
>  	}
>  
>  	if (arch_timer_mem_use_virtual)
> -		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_VIRT_SPI);
> +		irq = best_frame->virt_irq;
>  	else
> -		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_PHYS_SPI);
> +		irq = best_frame->phys_irq;
>  
> -	ret = -EINVAL;
>  	if (!irq) {
>  		pr_err("Frame missing %s irq",
>  		       arch_timer_mem_use_virtual ? "virt" : "phys");
> -		goto out;
> +		return -EINVAL;
>  	}
>  
> -	/*
> -	 * Try to determine the frequency from the device tree,
> -	 * if fail, get the frequency from CNTFRQ.
> -	 */
> -	if (!arch_timer_rate &&
> -	    of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
> -		arch_timer_detect_rate(base);
> +	base = ioremap(best_frame->cntbase, best_frame->size);
> +	if (!base) {
> +		pr_err("Can't map frame's registers\n");
> +		return -ENXIO;
> +	}
> +
> +	arch_timer_detect_rate(base);
>  
>  	ret = arch_timer_mem_register(base, irq);
> -	if (ret)
> +	if (ret) {
> +		iounmap(base);
> +		return ret;
> +	}
> +
> +	arch_counter_base = base;
> +	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
> +
> +	return 0;
> +}
> +
> +static int __init arch_timer_mem_of_init(struct device_node *np)
> +{
> +	struct arch_timer_mem *timer_mem;
> +	struct device_node *frame_node;
> +	struct resource res;
> +	int i, ret = -EINVAL;
> +
> +	timer_mem = kzalloc(sizeof(*timer_mem), GFP_KERNEL);
> +	if (!timer_mem)
> +		return -ENOMEM;
> +
> +	if (of_address_to_resource(np, 0, &res))
>  		goto out;
> +	timer_mem->cntctlbase = res.start;
> +	timer_mem->size = resource_size(&res);
>  
> -	return arch_timer_common_init();
> +	i = 0;
> +	for_each_available_child_of_node(np, frame_node) {
> +		int n;
> +		struct arch_timer_mem_frame *frame = &timer_mem->frame[i];
> +
> +		if (of_property_read_u32(frame_node, "frame-number", &n)) {
> +			pr_err("Missing frame-number\n");
> +			of_node_put(frame_node);
> +			goto out;
> +		}
> +		frame->frame_nr = n;
> +
> +		if (of_address_to_resource(frame_node, 0, &res)) {
> +			of_node_put(frame_node);
> +			goto out;
> +		}
> +		frame->cntbase = res.start;
> +		frame->size = resource_size(&res);
> +
> +		frame->virt_irq = irq_of_parse_and_map(frame_node,
> +						       ARCH_TIMER_VIRT_SPI);
> +		frame->phys_irq = irq_of_parse_and_map(frame_node,
> +						       ARCH_TIMER_PHYS_SPI);
> +
> +		if (++i >= ARCH_TIMER_MEM_MAX_FRAMES)
> +			break;
> +	}
> +	timer_mem->num_frames = i;
> +
> +	/* Try to determine the frequency from the device tree */
> +	if (!arch_timer_rate)
> +		of_property_read_u32(np, "clock-frequency", &arch_timer_rate);
> +
> +	ret = arch_timer_mem_init(timer_mem);
> +	if (!ret)
> +		ret = arch_timer_common_init();
>  out:
> -	iounmap(cntctlbase);
> -	of_node_put(best_frame);
> +	kfree(timer_mem);
>  	return ret;
>  }
>  CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
> -		       arch_timer_mem_init);
> +		       arch_timer_mem_of_init);
>  
>  #ifdef CONFIG_ACPI
>  static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags)
> -- 
> 2.7.4
> 
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fu.wei@linaro.org Nov. 23, 2016, 6:10 a.m. UTC | #2
Hi Mark,


On 19 November 2016 at 04:03, Mark Rutland <mark.rutland@arm.com> wrote:
> On Wed, Nov 16, 2016 at 09:49:03PM +0800, fu.wei@linaro.org wrote:
>> From: Fu Wei <fu.wei@linaro.org>
>>
>> The patch refactor original memory-mapped timer init code:
>>     (1) Extract a subfunction for detecting a bast time frame:
>>         is_best_frame.
>
> Please leave this logic in arch_timer_mem_init(). Pulling it out gains
> us nothing, but makes the patch harder to review.

OK, I have put it back to arch_timer_mem_init() in next version: v17

>
>>     (2) Refactor "arch_timer_mem_init", make it become a common code for
>>         memory-mapped timer init.
>>     (3) Add a new function "arch_timer_mem_of_init" for DT init.
>
> These generally look fine.
>
> Thanks,
> Mark.
>
>> Signed-off-by: Fu Wei <fu.wei@linaro.org>
>> ---
>>  drivers/clocksource/arm_arch_timer.c | 162 +++++++++++++++++++++++------------
>>  1 file changed, 107 insertions(+), 55 deletions(-)
>>
>> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
>> index 9ddc091..0836bb9 100644
>> --- a/drivers/clocksource/arm_arch_timer.c
>> +++ b/drivers/clocksource/arm_arch_timer.c
>> @@ -923,17 +923,35 @@ static int __init arch_timer_of_init(struct device_node *np)
>>  CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
>>  CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
>>
>> -static int __init arch_timer_mem_init(struct device_node *np)
>> +static bool __init is_best_frame(void __iomem *cntctlbase, u32 cnttidr, int n)
>> +{
>> +     u32 cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT | CNTACR_RWVT |
>> +                  CNTACR_RVOFF | CNTACR_RVCT;
>> +
>> +     /* Try enabling everything, and see what sticks */
>> +     writel_relaxed(cntacr, cntctlbase + CNTACR(n));
>> +     cntacr = readl_relaxed(cntctlbase + CNTACR(n));
>> +
>> +     if ((cnttidr & CNTTIDR_VIRT(n)) &&
>> +         !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT)))
>> +             arch_timer_mem_use_virtual = true;
>> +     else if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
>> +             return false;
>> +
>> +     return true;
>> +}
>> +
>> +static int __init arch_timer_mem_init(struct arch_timer_mem *timer_mem)
>>  {
>> -     struct device_node *frame, *best_frame = NULL;
>>       void __iomem *cntctlbase, *base;
>> -     unsigned int irq, ret = -EINVAL;
>> +     struct arch_timer_mem_frame *best_frame = NULL;
>> +     unsigned int irq;
>>       u32 cnttidr;
>> +     int i, ret;
>>
>> -     arch_timers_present |= ARCH_TIMER_TYPE_MEM;
>> -     cntctlbase = of_iomap(np, 0);
>> +     cntctlbase = ioremap(timer_mem->cntctlbase, timer_mem->size);
>>       if (!cntctlbase) {
>> -             pr_err("Can't find CNTCTLBase\n");
>> +             pr_err("Can't map CNTCTLBase.\n");
>>               return -ENXIO;
>>       }
>>
>> @@ -943,76 +961,110 @@ static int __init arch_timer_mem_init(struct device_node *np)
>>        * Try to find a virtual capable frame. Otherwise fall back to a
>>        * physical capable frame.
>>        */
>> -     for_each_available_child_of_node(np, frame) {
>> -             int n;
>> -             u32 cntacr;
>> -
>> -             if (of_property_read_u32(frame, "frame-number", &n)) {
>> -                     pr_err("Missing frame-number\n");
>> -                     of_node_put(frame);
>> -                     goto out;
>> -             }
>> -
>> -             /* Try enabling everything, and see what sticks */
>> -             cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT |
>> -                      CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT;
>> -             writel_relaxed(cntacr, cntctlbase + CNTACR(n));
>> -             cntacr = readl_relaxed(cntctlbase + CNTACR(n));
>> -
>> -             if ((cnttidr & CNTTIDR_VIRT(n)) &&
>> -                 !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) {
>> -                     of_node_put(best_frame);
>> -                     best_frame = frame;
>> -                     arch_timer_mem_use_virtual = true;
>> -                     break;
>> +     for (i = 0; i < timer_mem->num_frames; i++) {
>> +             if (is_best_frame(cntctlbase, cnttidr,
>> +                               timer_mem->frame[i].frame_nr)) {
>> +                     best_frame = &timer_mem->frame[i];
>> +                     if (arch_timer_mem_use_virtual)
>> +                             break;
>>               }
>> -
>> -             if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
>> -                     continue;
>> -
>> -             of_node_put(best_frame);
>> -             best_frame = of_node_get(frame);
>>       }
>> +     iounmap(cntctlbase);
>>
>> -     ret= -ENXIO;
>> -     base = arch_counter_base = of_iomap(best_frame, 0);
>> -     if (!base) {
>> -             pr_err("Can't map frame's registers\n");
>> -             goto out;
>> +     if (!best_frame) {
>> +             pr_err("Can't find frame for register\n");
>> +             return -EINVAL;
>>       }
>>
>>       if (arch_timer_mem_use_virtual)
>> -             irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_VIRT_SPI);
>> +             irq = best_frame->virt_irq;
>>       else
>> -             irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_PHYS_SPI);
>> +             irq = best_frame->phys_irq;
>>
>> -     ret = -EINVAL;
>>       if (!irq) {
>>               pr_err("Frame missing %s irq",
>>                      arch_timer_mem_use_virtual ? "virt" : "phys");
>> -             goto out;
>> +             return -EINVAL;
>>       }
>>
>> -     /*
>> -      * Try to determine the frequency from the device tree,
>> -      * if fail, get the frequency from CNTFRQ.
>> -      */
>> -     if (!arch_timer_rate &&
>> -         of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
>> -             arch_timer_detect_rate(base);
>> +     base = ioremap(best_frame->cntbase, best_frame->size);
>> +     if (!base) {
>> +             pr_err("Can't map frame's registers\n");
>> +             return -ENXIO;
>> +     }
>> +
>> +     arch_timer_detect_rate(base);
>>
>>       ret = arch_timer_mem_register(base, irq);
>> -     if (ret)
>> +     if (ret) {
>> +             iounmap(base);
>> +             return ret;
>> +     }
>> +
>> +     arch_counter_base = base;
>> +     arch_timers_present |= ARCH_TIMER_TYPE_MEM;
>> +
>> +     return 0;
>> +}
>> +
>> +static int __init arch_timer_mem_of_init(struct device_node *np)
>> +{
>> +     struct arch_timer_mem *timer_mem;
>> +     struct device_node *frame_node;
>> +     struct resource res;
>> +     int i, ret = -EINVAL;
>> +
>> +     timer_mem = kzalloc(sizeof(*timer_mem), GFP_KERNEL);
>> +     if (!timer_mem)
>> +             return -ENOMEM;
>> +
>> +     if (of_address_to_resource(np, 0, &res))
>>               goto out;
>> +     timer_mem->cntctlbase = res.start;
>> +     timer_mem->size = resource_size(&res);
>>
>> -     return arch_timer_common_init();
>> +     i = 0;
>> +     for_each_available_child_of_node(np, frame_node) {
>> +             int n;
>> +             struct arch_timer_mem_frame *frame = &timer_mem->frame[i];
>> +
>> +             if (of_property_read_u32(frame_node, "frame-number", &n)) {
>> +                     pr_err("Missing frame-number\n");
>> +                     of_node_put(frame_node);
>> +                     goto out;
>> +             }
>> +             frame->frame_nr = n;
>> +
>> +             if (of_address_to_resource(frame_node, 0, &res)) {
>> +                     of_node_put(frame_node);
>> +                     goto out;
>> +             }
>> +             frame->cntbase = res.start;
>> +             frame->size = resource_size(&res);
>> +
>> +             frame->virt_irq = irq_of_parse_and_map(frame_node,
>> +                                                    ARCH_TIMER_VIRT_SPI);
>> +             frame->phys_irq = irq_of_parse_and_map(frame_node,
>> +                                                    ARCH_TIMER_PHYS_SPI);
>> +
>> +             if (++i >= ARCH_TIMER_MEM_MAX_FRAMES)
>> +                     break;
>> +     }
>> +     timer_mem->num_frames = i;
>> +
>> +     /* Try to determine the frequency from the device tree */
>> +     if (!arch_timer_rate)
>> +             of_property_read_u32(np, "clock-frequency", &arch_timer_rate);
>> +
>> +     ret = arch_timer_mem_init(timer_mem);
>> +     if (!ret)
>> +             ret = arch_timer_common_init();
>>  out:
>> -     iounmap(cntctlbase);
>> -     of_node_put(best_frame);
>> +     kfree(timer_mem);
>>       return ret;
>>  }
>>  CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
>> -                    arch_timer_mem_init);
>> +                    arch_timer_mem_of_init);
>>
>>  #ifdef CONFIG_ACPI
>>  static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags)
>> --
>> 2.7.4
>>
diff mbox

Patch

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 9ddc091..0836bb9 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -923,17 +923,35 @@  static int __init arch_timer_of_init(struct device_node *np)
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
 CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
 
-static int __init arch_timer_mem_init(struct device_node *np)
+static bool __init is_best_frame(void __iomem *cntctlbase, u32 cnttidr, int n)
+{
+	u32 cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT | CNTACR_RWVT |
+		     CNTACR_RVOFF | CNTACR_RVCT;
+
+	/* Try enabling everything, and see what sticks */
+	writel_relaxed(cntacr, cntctlbase + CNTACR(n));
+	cntacr = readl_relaxed(cntctlbase + CNTACR(n));
+
+	if ((cnttidr & CNTTIDR_VIRT(n)) &&
+	    !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT)))
+		arch_timer_mem_use_virtual = true;
+	else if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
+		return false;
+
+	return true;
+}
+
+static int __init arch_timer_mem_init(struct arch_timer_mem *timer_mem)
 {
-	struct device_node *frame, *best_frame = NULL;
 	void __iomem *cntctlbase, *base;
-	unsigned int irq, ret = -EINVAL;
+	struct arch_timer_mem_frame *best_frame = NULL;
+	unsigned int irq;
 	u32 cnttidr;
+	int i, ret;
 
-	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
-	cntctlbase = of_iomap(np, 0);
+	cntctlbase = ioremap(timer_mem->cntctlbase, timer_mem->size);
 	if (!cntctlbase) {
-		pr_err("Can't find CNTCTLBase\n");
+		pr_err("Can't map CNTCTLBase.\n");
 		return -ENXIO;
 	}
 
@@ -943,76 +961,110 @@  static int __init arch_timer_mem_init(struct device_node *np)
 	 * Try to find a virtual capable frame. Otherwise fall back to a
 	 * physical capable frame.
 	 */
-	for_each_available_child_of_node(np, frame) {
-		int n;
-		u32 cntacr;
-
-		if (of_property_read_u32(frame, "frame-number", &n)) {
-			pr_err("Missing frame-number\n");
-			of_node_put(frame);
-			goto out;
-		}
-
-		/* Try enabling everything, and see what sticks */
-		cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT |
-			 CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT;
-		writel_relaxed(cntacr, cntctlbase + CNTACR(n));
-		cntacr = readl_relaxed(cntctlbase + CNTACR(n));
-
-		if ((cnttidr & CNTTIDR_VIRT(n)) &&
-		    !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) {
-			of_node_put(best_frame);
-			best_frame = frame;
-			arch_timer_mem_use_virtual = true;
-			break;
+	for (i = 0; i < timer_mem->num_frames; i++) {
+		if (is_best_frame(cntctlbase, cnttidr,
+				  timer_mem->frame[i].frame_nr)) {
+			best_frame = &timer_mem->frame[i];
+			if (arch_timer_mem_use_virtual)
+				break;
 		}
-
-		if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT))
-			continue;
-
-		of_node_put(best_frame);
-		best_frame = of_node_get(frame);
 	}
+	iounmap(cntctlbase);
 
-	ret= -ENXIO;
-	base = arch_counter_base = of_iomap(best_frame, 0);
-	if (!base) {
-		pr_err("Can't map frame's registers\n");
-		goto out;
+	if (!best_frame) {
+		pr_err("Can't find frame for register\n");
+		return -EINVAL;
 	}
 
 	if (arch_timer_mem_use_virtual)
-		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_VIRT_SPI);
+		irq = best_frame->virt_irq;
 	else
-		irq = irq_of_parse_and_map(best_frame, ARCH_TIMER_PHYS_SPI);
+		irq = best_frame->phys_irq;
 
-	ret = -EINVAL;
 	if (!irq) {
 		pr_err("Frame missing %s irq",
 		       arch_timer_mem_use_virtual ? "virt" : "phys");
-		goto out;
+		return -EINVAL;
 	}
 
-	/*
-	 * Try to determine the frequency from the device tree,
-	 * if fail, get the frequency from CNTFRQ.
-	 */
-	if (!arch_timer_rate &&
-	    of_property_read_u32(np, "clock-frequency", &arch_timer_rate))
-		arch_timer_detect_rate(base);
+	base = ioremap(best_frame->cntbase, best_frame->size);
+	if (!base) {
+		pr_err("Can't map frame's registers\n");
+		return -ENXIO;
+	}
+
+	arch_timer_detect_rate(base);
 
 	ret = arch_timer_mem_register(base, irq);
-	if (ret)
+	if (ret) {
+		iounmap(base);
+		return ret;
+	}
+
+	arch_counter_base = base;
+	arch_timers_present |= ARCH_TIMER_TYPE_MEM;
+
+	return 0;
+}
+
+static int __init arch_timer_mem_of_init(struct device_node *np)
+{
+	struct arch_timer_mem *timer_mem;
+	struct device_node *frame_node;
+	struct resource res;
+	int i, ret = -EINVAL;
+
+	timer_mem = kzalloc(sizeof(*timer_mem), GFP_KERNEL);
+	if (!timer_mem)
+		return -ENOMEM;
+
+	if (of_address_to_resource(np, 0, &res))
 		goto out;
+	timer_mem->cntctlbase = res.start;
+	timer_mem->size = resource_size(&res);
 
-	return arch_timer_common_init();
+	i = 0;
+	for_each_available_child_of_node(np, frame_node) {
+		int n;
+		struct arch_timer_mem_frame *frame = &timer_mem->frame[i];
+
+		if (of_property_read_u32(frame_node, "frame-number", &n)) {
+			pr_err("Missing frame-number\n");
+			of_node_put(frame_node);
+			goto out;
+		}
+		frame->frame_nr = n;
+
+		if (of_address_to_resource(frame_node, 0, &res)) {
+			of_node_put(frame_node);
+			goto out;
+		}
+		frame->cntbase = res.start;
+		frame->size = resource_size(&res);
+
+		frame->virt_irq = irq_of_parse_and_map(frame_node,
+						       ARCH_TIMER_VIRT_SPI);
+		frame->phys_irq = irq_of_parse_and_map(frame_node,
+						       ARCH_TIMER_PHYS_SPI);
+
+		if (++i >= ARCH_TIMER_MEM_MAX_FRAMES)
+			break;
+	}
+	timer_mem->num_frames = i;
+
+	/* Try to determine the frequency from the device tree */
+	if (!arch_timer_rate)
+		of_property_read_u32(np, "clock-frequency", &arch_timer_rate);
+
+	ret = arch_timer_mem_init(timer_mem);
+	if (!ret)
+		ret = arch_timer_common_init();
 out:
-	iounmap(cntctlbase);
-	of_node_put(best_frame);
+	kfree(timer_mem);
 	return ret;
 }
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
-		       arch_timer_mem_init);
+		       arch_timer_mem_of_init);
 
 #ifdef CONFIG_ACPI
 static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags)